1. Field of the Invention
The present invention relates to a printing apparatus and a cleaning method and, more particularly, to an inkjet printing apparatus and a cleaning method of wiping the orifice surface of an inkjet printhead mounted in the apparatus.
2. Description of the Related Art
Ink may stick to a surface (to be referred to as an orifice surface hereinafter) where orifices are formed in a printhead mounted in an inkjet printing apparatus (to be referred to as a printing apparatus hereinafter) and impede normal discharge. To prevent such a failure, the printing apparatus generally includes a wiping unit configured to wipe ink sticking to the orifice surface. To wipe the orifice surface, the wiping unit includes, for example, a wiping member made of an elastic material and a contact member used to make the wiping member contact the orifice surface. A wiping operation is performed by making the wiping member contact the orifice surface and slide at a predetermined timing.
In a so-called serial printing apparatus which performs printing by discharging ink to a printing medium while reciprocally moving a carriage with a printhead mounted on it, a method of wiping the orifice surface by moving the contact member during suspension of the reciprocating motion is known. There is also known a method of wiping the orifice surface by moving the printhead in a state in which the contact member is in contact. The latter wiping method is effective especially when the wiping frequency is high. That is, since the wiping operation can be performed during the reciprocating motion of the carriage, a single wiping operation can be done in a short time as compared to the method of performing the wiping operation during suspension of the reciprocating motion of the carriage.
Japanese Patent Laid-Open No. 2005-21809 discloses an example in which a sheet-like wiping member is made to slide in the vertical direction against the orifice array of the printhead, thereby performing wiping. The sheet-like wiping member is known to exert a greater wiping effect than a wiping method of causing a so-called wiper blade to slide.
As the inkjet printing apparatuses and printing methods thereof have diversified in recent years, printing using a plurality of color inks or inks reactive with each other may be done by a single or a plurality of printheads. In this case, if the wiping operation is performed by a single wiping member, an ink may mix in the orifices of another ink, and color mixing or an ink discharge failure due to solidification by reaction may occur.
In the method disclosed in Japanese Patent Laid-Open No. 2005-21809, the sheet-like wiping member is wound, thereby preventing an ink discharge failure due to color mixing and ink solidification by reaction from occurring. However, the effect is not sufficient.